• KIPS Transactions on Software and Data Engineering
• /
• v.9 no.1
• /
• pp.11-16
• /
• 2020

3D printing is one of the emerging technologies and getting a lot of attention. To do 3D printing, 3D model is first generated, and then converted to G-code which is 3D printer's operations. Facet, which is a small triangle, represents a small surface of 3D model. Depending on the height or precision of the 3D model, the number of facets becomes very large and so the conversion time from 3D model to G-code takes longer. Apach Hadoop is a software framework to support distributed processing for large data set and its application range gets widening. In this paper, Hadoop is used to do the conversion works time-efficient way. 2-phase distributed algorithm is developed first. In the algorithm, all facets are sorted according to its lowest Z-value, divided into N parts, and converted on several nodes independently. The algorithm is implemented in four steps; preprocessing - Map - Shuffling - Reduce of Hadoop. Finally, to show the performance evaluation, Hadoop systems are set up and converts testing 3D model while changing the height or precision.

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.47 no.2
• /
• pp.100-105
• /
• 2010

In this paper, a FM radio receiver integrated circuit has been developed based on $0.5{\mu}m$ CMOS process for Zero-Crossing FM demodulator over the 88MHz to 108MHz band. The receiver is designed with the low-IF architecture, and includes Low Noise Amplifier(LNA), Down-Conversion Mixer, Phase Locked Loop(PLL), IF LPF, and a comparator. The measured results of the LNA and Mixer show that the conversion gain of 23.2 dB, the input PldB of -14 dBm, and the noise figure of 15 dB. The measured analog block of the LPF and comparator show the voltage gain of over 89 dB, and the IF LPF can configure the passband from 600KHz to 1.3MHz with 100KHz step through the internal control register banks. The designed FM radio receiver operates at 4.5V with the total current consumption of 15.3mA, so the total power consumption is about 68.85mW. The commercial FM radio has been successfully received.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.52 no.2
• /
• pp.50-54
• /
• 2015

In this paper, we report on a high performance 94 GHz MMIC mixer module using 0.1-um metamorphic high electron mobility transistors (MHEMTs). A modified resistive mixer with a RF amplifier was proposed in this work for low conversion loss and high LO-RF isolation. The MMIC mixer module was fabricated using a MMIC chip and CPW-waveguide transitions. The fabricated mixer chip and module showed a low conversion loss of 6.3 dB and 9.5 dB, and LO-RF isolations of 24.8 and 30.4 dB at 94 GHz, respectively. This results are superior to those of previously W-band (75-110 GHz) MMIC mixers.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.9 no.2
• /
• pp.249-254
• /
• 2004

Dietary supplementation of sodium nitrate with different concentrations 50, 100, 200, 500, 700 and 1000 $\mu\textrm{g}$/ml of single, two, three and four feeds to fifth instar larvae of biovoltine NB$_4$D$_2$ race of the silkworm, B. mori resulted in significant increase in the food conversion, conversion rate and conversion efficiency $K_1$ and $K_2$. However, there were significant decrease in the food assimilation, assimilation rate and assimilation efficiency in the sodium nitrate treated groups as compared with that of the corresponding parameters of the carrier control. This indicates that the administration of sodium nitrate may stimulate metabolic activities, thereby influencing conversion of food into body weight in the bivoltine silkworm, B. mori.

• JSTS:Journal of Semiconductor Technology and Science
• /
• v.14 no.2
• /
• pp.246-251
• /
• 2014

In this paper, a high-speed CMOS Image Sensor (CIS) based on a 10-bit two step Single Slope A/D Converter (SS-ADC) is proposed. The A/D converter is composed of both 5-bit coarse ADC and a 6-bit fine ADC, and the conversion speed is 10 times faster than that of the single-slope A/D convertor. In order to reduce the pixel noise, further, a Hybrid Correlated Double Sampling (H-CDS) is also discussed. The proposed A/D converter has been fabricated with 0.13um 1-poly 4-metal CIS process, and it has a QVGA ($320{\times}240$) resolution. The fabricated chip size is $5mm{\times}3mm$, and the power consumption is about 35 mW at 3.3 V supply voltage. The measured conversion speed is 10 us, and the frame rate is 220 frames/s.

• Proceedings of the Korea Institute of Convergence Signal Processing
• /
• 2003.06a
• /
• pp.110-113
• /
• 2003

In this paper, the multi-channel high speed data acquisition system is implemented. This high speed signal processing system for 3-D image display is applicable to the manipulation of a medical image processing, multimedia data and various fields of digital image processing. In order to convert the analog signal into digital one, A/D conversion circuit is designed. PCI interface method is designed and implemented, which is capable of transmission a large amount of data to computer. In order to, especially, channel extendibility of images acquisition, bus communication method is selected. By using this bus method, we can interface each module effectively. In this paper, 32-channel A/D conversion and PCI interface system for 3-dimensional and real-time display of the retina image is developed. The 32-channel image acquisition system and high speed data transmission system developed in this paper is applicable to not only medical image processing as 3-D representation of retina image but also various fields of industrial image processing in which the multi-point realtime image acquisition system is needed.

• ETRI Journal
• /
• v.27 no.3
• /
• pp.312-318
• /
• 2005

Mid-span spectral inversion (MSSI) has to utilize high optical pump power, for its operation principle is based on a nonlinear optical wavelength conversion. In this paper, a low pump-power operation of MSSI-based chromatic dispersion compensation (CDC) has been achieved successfully, for the first time to our knowledge, by introducing a noise pre-reduction scheme in cascaded wavelength conversions with periodically poled $LiNbO_3$ waveguides at a relatively low operation temperature. As preliminary studies, phase-matching properties and operation-temperature dependence of the wavelength converter (WC) were characterized. The WC pumped at 1549 nm exhibited a wide conversion bandwidth of 59 nm covering the entire C-band and a conversion efficiency of -23.6 dB at 11 dBm pump power. CDC experiments were implemented with 2.5 and 10 Gb/s transmission systems over 100 km single-mode fiber. Although it is well-known that the signal distortion due to chromatic dispersion is not critical at a 2.5 Gb/s transmission, the clear recovery of eye patterns was identified. At 10 Gb/s transmission experiments, eye patterns were retrieved distinctly from seriously distorted ones, and notable improvements in bit-error rates were acquired at a low pump power of 14 dBm.

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.43 no.4 s.346
• /
• pp.8-15
• /
• 2006

In this paper, the 94 GHz, low conversion loss, and high isolation single balanced mixer is designed and fabricated using GaAs-based metamorphic high electron mobility transistors (MHEMTs) with 70 nm gate length and the hybrid ring coupler with the micromachined transmission lines, dielectric-supported air-gapped microstrip lines (DAMLs). The 70 nm MHEMT devices exhibit DC characteristics with a drain current density of 607 mA/mm an extrinsic transconductance of 1015 mS/mm. The current gain cutoff frequency ($f_T$) and maximum oscillation frequency ($f_{max}$) are 320 GHz and 430 GHz, respectively. The fabricated hybrid ring coupler shows wideband characteristics of the coupling loss of $3.57{\pm}0.22dB$ and the transmission loss of $3.80{\pm}0.08dB$ in the measured frequency range of 85 GHz to 105 GHz. This mixer shows that the conversion loss and isolation characteristics are $2.5dB{\sim}>2.8dB$ and under -30 dB, respectively, in the range of $93.65GHz{\sim}94.25GHz$. At the center frequency of 94 GHz, this mixer shows the minimum conversion loss of 2.5 dB at a LO power of 6 dBm To our knowledge, these results are the best performances demonstrated from 94 GHz single balanced mixer utilizing GaAs-based HEMTs in terms of conversion loss as well as isolation characteristics.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
• /
• 2002.11a
• /
• pp.77-81
• /
• 2002

This paper demonstrates a CMOS downconversion mixer for 2.4GHz ISM band applications. The mixer, implemented in a 0.18um CMOS process, is based on the CMOS Gilbert Cell mixer, With a 2.5GHz local oscillator and a 2.45GHz RF input, the measurement results exhibit power conversion gam of -6dB, IIP3 of -6dBm, input $P_{-1dB}$ of -15 dBm, and power dissipation in mixer core of 2.7 mW with 0㏈m LO power and 1.8V supply voltage.

• Journal of Digital Convergence
• /
• v.12 no.12
• /
• pp.521-528
• /
• 2014

In this paper, we propose the method of converting 2D image to 3D image using linear curves in HTML5. We use only one image without any other information about depth map for creating 3D images. So we filter the original image to extract RGB colors for left and right eyes. After selecting the ready-made control point of linear curves to set up depth values, users can set up the depth values and modify them. Based on the depth values that the end users select, we reflect them. Anaglyph 3D is automatically made with the whole and partial depth information. As all of this work has been designed and implemented in Web environment using HTML5, it is very easy and convenient and end users can create any 3D image that they want to make.